The embodiments described herein relate generally to methods and systems for assembling a wind turbine including a blade extension, and more particularly, to systems and methods for assembling a blade extension assembly for use in a wind turbine.
At least some known wind turbine towers include a nacelle fixed atop a tower, wherein the nacelle includes a rotor coupled to a generator through a shaft. In known rotor assemblies, a plurality of blades extend from the rotor. The blades are oriented such that wind passing over the blades turns the rotor and rotates the shaft, thereby driving the generator to generate electricity.
As air passes over each blade, a pressure differential results on opposing sides of the blade, such that a higher pressure is generated on one side and a lower pressure is generated on the opposite side. Because of this pressure differential, air tends to curl around the blade tip to establish pressure equilibrium. The generation of vortices at the blade tip is facilitated by the air curling around the blade tip, and the flow of air over the blade combines with the vortices at the blade tip to generate a string of vortices that trail from the blade tip.
Blades with a high aerodynamic loading generate increased lift, and the increased lift tends to increase the efficiency of the blade. However, blades with increased loading also tend to have a greater surface area at the blade tip, which may contribute to stronger vortices being generated at the blade tip. The increased strength of the vortices and the interaction of each vortex with the blade surface can increase the noise generated by the turbine. Additionally, turbulent kinetic energy (TKE) at the blade tip increases pressure fluctuations that are responsible for noise generation. Moreover, when the flow of air separates from the blade tip, the blade surface area is “washed” by the resulting vortices, thereby generating additional noise.